Guide and alignment member

ABSTRACT

A guide and alignment member for use in serial printing devices. The guide member makes possible a sizable increase in the number of type that may be printed in a given time frame. As the type elements approach the printing impact zone at high speed, some of them may still be oscillating from a previous impact, or may be misaligned. As these misaligned or vibrating elements move towards the impact zone, the guide member brings these elements into registry with the printing hammer. The result of this guiding process allows for greater speed of operation, since the type elements will be prevented for interfering or otherwise colliding with the striking hammer.

United States Patent 1191 Kittredge I GUIDE AND ALIGNMENT MEMBER ['75]Inventor: Lloyd G. Kittredge, Trumbull,

Conn.

[73] Assignee: Pitney-Bowes, lnc., Stamford, Conn. [22] Filed: June 18,1973 211' Appl. No.: 371,151

' 52 U. S. c1. 197/53 [-51] Int. Cl.....- B4lj 1/32 [58] Field of Search197/18, 52, 53, 55, '48,

[56] References Cited UNITED STATES PATENTS 3,355,001 ll/1967 Reed .etal.. 197/53 X 3,371,766 3/1968 Staller 197/53 3,442,365 I 5/l969 Raglandet al 197/53 3,731,779 I 5/l973. Kondur 197/49 X 3,760,925 /l973 Bossil97/53 [111 3, 40,105 [451 Oct. 8, 1974 Primary Iiraminer-Robert E.Pulfrey Assistant Examiner-R. T. Raider Attorney, Agent, or Firm-WilliamD. Soltow, Jr.; Albert W. Scribner; Robert S. Solzman [57] ABSTRACT Aguide and alignment member for use in serial printing devices. The guidemember makes possible a sizable increase in the number of type that maybe printed in a given time frame. As the type elements approach theprinting impact zone at high speed, some of them may still beoscillating from a previous impact, or may be misaligned. As thesemisaligned or vi- 1 Claim, 3, Drawing Figures PATENTEDBET 818143.840.105

FIGJ

FIG.2

1 GUIDE AND ALIGNMENT MEMBER The invention pertains to serial printingdevices, and more particularly to high speed serial printers havingprintfonts arranged upon a disc member which rotates the fonts past animpacting printing hammer.

Heretofore, several problems have been detected with high speed serialprinters of the disc type. It has been noticed that after some time theprinting fingers on the disc will tend to take a set, resulting in anuneven collimation of the printing fingers. Also, unless the printingdisc is made to exacting tolerances, some of the printing fingers willbe initially misaligned.

These misalignments contribute to uneven printing operation.

It has been noticed that an impacted printing finger will be put intovibration upon its return from its contact with the platen. Now, at lowspeed, the vibrations of the finger will sufficiently damp out as theprinting disc rotates to new and subsequent print positions. As aresult, no interference is encountered with the impacting hammer as thevibrating fingers move past the print hammer.

However, as the speed of operation is increased, interference with theprint hammer is observed. This is so, because the perturbations of thepreviously struck printing fingers have not had time to sufficientlydissipate as the disc moves back and forth between print positions. i

The present invention seeks to correct alllof these aforementioneddifficulties by guiding and'alignin'g the fingers as they approach theimpacting zone.

The invention comprises a wire-like member which is rigidly positionedabout the printing hammer. This wire-like member comes in contact withthe printing fingers approaching the printing. station, so as tostraighten and align them, and force them into registry with-the head ofthe print hammer. Not only are the fingers aligned and straightened, butthey are forced out of a collision course with the reciprocating printhammer. Thus, the problem of hammer-finger interference is eliminated.

Another very useful advantage is likewise achieved by use of this guidemember. The guide and alignment bar serves to position all the printingfingers at a given set position before impact is achieved, wherebyimpact energy is controlled to a greater degree. This results inproviding even and uniform character imprinting.

Use, of the guide bar also has the advantage, in that the initialprinting disc tolerances need not be as critical, and thus the cost ofthe printing disc is reduced.

It is an object of this invention to provide an improved serial printingapparatus;

It is another object of the'invention to provide a serial printingapparatus capable of trouble-free, high speed operation;

It is yetanother object of this invention to provide a low-cost serialprinting apparatus; and

(arrows 16) as depicted in FIG. 2, the dihedral sections It is stillanother object of the invention to provide a means to control impactenergy of disc printing fingers.

These and other objects of this invention will be bet ter understood andbecome more apparent with reference to the following detaileddescription and accompanying drawings, in which:

FIG. 1 is a prospective view of the guide and alignment member of thisinvention shown in situ;

FIG. 2 is a top view of the printing hammer and disc of a serial printerwithout the guide bar of this invention; and

FIG. 2a is a top view of the hammer and disc arrangement of FIG. 2 withthe guide bar of the invention.

Generally speaking, the invention is for use in a serial printingapparatus comprising a printing hammer supported by a base member. Theprinting hammer is movable towards a printing station, where it contactsone of a plurality of type elements stationed at the printing station.The type elements move serially past the hammer until the desired typeelement arrives at the print station for printing. Means, such as asolenoid, is provided to actuate the print hammer.

The invention is for a guide member for guiding and aligning the typeelements as they move towards the printing station. Theguide member issubstantially adjacent the hammer and is disposed in such a way as tocontact a portion of at least one type element moving transversely of,and approaching the impact axis of the hammer.

Now referring to FIG. 1, a serial printing apparatus containing theinvention is depicted. A base member- 10 is shown which supports aprinting hammer l1 illustrated in cutaway view. A disc 14 is made torotate past the printing hammer as depicted by arrows 16. The disc canmove in either clockwise or counterclockwise direction in seeking thenext type to be printed. Thus, the correct type is located much sooner,than if the disc rotated in only one direction. The disc 14 contains aplurality of type elements or fingers 15 which each contain a character,and which radiate outwardly from a hub portion 17. The hub 17 of thedisc is connected by shaft 18 to a stepping motor 29, which turns thedisc.

The hammer 11 is caused to move towards the disc 14 as shown byarrow'2l,' when a desired type to be printed is stationed opposite theprint hammer. The print hammer has a female dihedral printing head 22,which conforms with the male dihedral head 23 of the printing fingers15. e

The guide and alignment bar 20 of this invention is fastened at its endsupon base member 10 by means of screw fasteners 19. v Y

The bar 20 generally curves inwardly from either end towards the typefingers 15. The mid-portion of the bar, generally illustrated by arrow-30 is substantially straight.

Operation of the Device Operation of the invention will be describedwith reference to FIGS. 2 and 2a. FIG. 2 shows the hammer and discarrangement aforementioned without the guide bar 20. FIG. 2a shows thesame arrangement with the guide bar.

As the disc 14 is made to traverse past hammer 21 23 of fingers 15 whichare misaligned or in a vibratory state, will be caused to interfere withapproaching ham- 3 mer 11 as it comes forward (arrow 21) to provide forthe next contact.

When the speed of operation increases, the incidence of a collisionbetween the fingers 15 and the hammer I 11 is greater.

FIG. 2a illustrates the inventive solution to the above problem. Thewire-like bar forces, by means of contact with the incoming fingers 15,all the sections 23 into a straight column. Since the mid-portion 30 ofthe bar 20 is substantially straight and projects the dihedral sections23 of the fingers ahead of the hammer 11, collision or interference ofthese parts is precluded. Because all of the type sections 23 are causedto align as shown, each are struck having the same distance from theplaten (not shown). This provides an evenness of print, assuming othercompensating factors regarding type face area are provided.

It has thus been demonstrated, that the present invention will fulfillall the objects subscribed to hereinbefore.

As will be obvious to any skilled practitioner, there are manymodifications to the invention which will present themselves.

For example, fasteners 19 may be any suitable attaching means inaddition to the screws illustrated. Bar 20 can take the shape of awire-or bar-like element. Means may also be provided for changing thedistance of the bar and disc with respect to the platen and each other.Friction reducing materials maybe employed to provide a smoothness ofoperation of the contacting parts, and the curved portions of the barcan be made more or less steep as needed, for faster or sloweroperatron.

All such modifications as naturally occur to those skilled in the art,are deemed to fall within the purview and scope of the intendedinvention as presented by the appended claims. The illustrativeembodiment depicted in the attached drawings is considered merely as anexemplary representation of one of the ways of practicing the invention.I

What is claimed is:

1. A guide and alignment apparatus for use in a serial-type printingdevice comprising a printing hammer for impacting a plurality of typeelements disposed upon a rotatable disc moving transversely of an axialimpact axis of said printing hammer, said guide and alignment apparatuscomprising:

a base member for supporting said printing hammerfor axial movementalong said impact axis; and

a curvilinear guide and alignment member supported by said base memberin substantially adjacent relationship with said printing hammer and sodisposed as to contact a number of type elements as said type elementsmove transversely of, and approach said impact axis of the printinghammer, said guide and alignment member comprising a section of wirewhich is fastened at its ends to said base, said wire curving inwardlytowards said type elements and having a substantially straightmid-portion disposed transversely adjacent said impact axis of theprinting hammer and contacting and supporting a number of type elementsas they approach the impact axis of said printing hammer, said guide andalignment member aligning said type elements at a given set positionbefore impact is achieved.

1. A guide and alignment apparatus for use in a serial-type printingdevice comprising a printing hammer for impacting a plurality of typeelements disposed upon a rotatable disc moving transversely of an axialimpact axis of said printing hammer, said guide and alignment apparatuscomprising: a base member for supporting said printing hammer for axialmovement along said impact axis; and a curvilinear guide and alignmentmember supported by said base member in substantially adjacentrelationship with said printing hammer and so disposed as to contact anumber of type elements as said type elements move transversely of, andapproach said impact axis of the printing hammer, said guide andalignment member comprising a section of wire which is fastened at itsends to said base, said wire curving inwardly towards said type elementsand having a substantially straight mid-portion disposed transverselyadjacent said impact axis of the printing hammer and contacting andsupporting a number of type elements as they approach the impact axis ofsaid printing hammer, said guide and alignment member aligning said typeelements at a given set position before impact is achieved.